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When to Plant Celery in Monterey County, CA

Celery is a marshland plant that requires consistent moisture and cool temperatures to produce crisp, flavorful stalks. It is a rewarding but demanding garden crop.

Monterey County, California is in USDA Zone 9b. The average last spring frost is March 13 and the first fall frost is November 17, giving you a growing season of approximately 249 days.

At an elevation of 260 feet, Monterey County receives approximately 12.5 inches of rainfall annually with predominantly loam soil. Summer highs average 93ยฐF, providing good warmth for Celery during the growing season. With low rainfall, drip irrigation is essential for growing Celery successfully. Mulch heavily to conserve soil moisture.

Monterey County, CA (Zone 9b) Long season
249 days
Last Spring Frost March 13
249 growing days
First Fall Frost November 17

Monterey County Soil Profile

Soil Type

Loam

Soil pH

6.7-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (108 days to spare)
Start indoors: Jan 30 Transplant: Feb 27 🍅 Harvest: May 22 – Jul 17
Recommended (50%) ✓ Fits season (109 days to spare)
Start indoors: Feb 13 Transplant: Mar 13 🍅 Harvest: Jun 5 – Jul 31
Safe Start (90%) ✓ Fits season (74 days to spare)
Start indoors: Apr 19 Transplant: May 17 🍅 Harvest: Aug 9 – Oct 4

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Monterey County

How your county's soil matches Celery's growing requirements.

Soil pH

Your soil pH (6.7โ€“7.2) overlaps with Celery's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The loam soil in Monterey County is excellent for Celery โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Celery.

How to Plant Celery

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Celery

3
successive plantings in your 249-day season

Sow every 9.1 weeks. Last sowing by Jul 20 to harvest before frost.

For a dedicated fall crop, sow by Sep 22.

Plant Water Budget

Plant needs
1.3″/week
Rainfall provides
0.2″/week
You supply
1.3″/week
Watering frequency 2-3 times/week
Season total 2,896 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Celery

Celery needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.

Month Celery Needs Rainfall You Supplement Action
Jan โ€” 2.7" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar 5.6" 2.1" 3.5" ๐Ÿšฟ Regular watering
Apr 5.6" 1" 4.6" ๐Ÿšฟ Regular watering
May 5.6" 0.3" 5.3" ๐Ÿšฟ Regular watering
Jun 5.6" 0.1" 5.5" ๐Ÿšฟ Regular watering
Jul 5.6" 0" 5.6" ๐Ÿšฟ Regular watering
Aug 5.6" 0" 5.6" ๐Ÿšฟ Regular watering
Sep 5.6" 0.1" 5.5" ๐Ÿšฟ Regular watering
Oct 5.6" 0.5" 5.1" ๐Ÿšฟ Regular watering
Nov 5.6" 1.2" 4.4" ๐Ÿšฟ Regular watering
Dec โ€” 1.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Monterey County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Celery Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Celery needs ~1,975 GDD — county provides 4,917 GDD Excellent fit

Celery Planting Timeline โ€” Monterey County, CA

Celery Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 โ€“ Feb 27
Transplant Outdoors March 13 Mar 13 โ€“ Mar 27
Direct Sow February 20 Feb 20 โ€“ Mar 13
Harvest June 5 Jun 5 โ€“ Jul 31
Fall Sowing September 22 Sep 22 โ€“ Oct 6

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors Direct Sow
March Transplant Outdoors Direct Sow
April โ€”
May โ€”
June Harvest
July Harvest
August โ€”
September Fall Sowing
October Fall Sowing
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.3"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

80โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 9b

๐Ÿ“† Growing Season

249 days in Monterey County

Growing Tips for Celery in Monterey County

Direct sow Celery outdoors after March 13 in Monterey County when soil has warmed and frost danger has passed.

Common pests for Celery in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

Monterey County receives only 12" of rain annually. Celery needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 10-12 weeks before last frost. Keep soil consistently moist and never let it dry out. Blanch stalks by mounding soil or using collars for milder flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celery in Monterey County, CA?

Monterey County is in Zone 9b with an average last frost of March 13. Plan your Celery planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Monterey County, CA?

Monterey County, California is in USDA Hardiness Zone 9b. The average last spring frost is March 13 and first fall frost is November 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Monterey County gardeners in Zone 9b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Monterey County, CA. Local conditions may vary. Last updated: April 2026.